Closing block with percussion safety for automatic guns



Aug. 16, 1955 s. FIORINI 2,715,356

CLOSING BLOCK WITH PERCUSSION SAFETY FOR AUTOMATIC GUNS Filed March 9,1950 2 Sheets-Sheet l Fig. 2 ;:f:

/ I l W 5a 5 O 4 6 7 I! 3 40 42 39 30 29 Fig.3 17 18 20 19 INVENTOR.SESTIUO F IORDNI ATTDRNEY Aug. 16, 1955 s FlQRlNl 2,715,356

CLOSING BLOCK WITH PERCUSSION SAFETY FOR AUTOMATIC GUNS Filed March 9,1950 2 Sheets-Sheet 2 Fig.5

INVENTOR. SESTILIO FIORINI ATTORNEY CLOSING BLOCK WITH PERCUSSION SAFETYFGR AUTOMATIC GUNS Sestilio Fiorini, Brescia, Italy, assignor to SocietaItaliana illltglnesto Breda per Costruzioni Meccaniche, Milan,

Application March 9, 1950, Serial No. 148,549

Claims priority, application Italy March 17, 1949 1 Claim. (Cl. 89-164)The present invention relates to automatic guns and more particularly tosafety devices for automatic guns.

The purpose of the present invention is to provide a locking block foran automatic gun which will also provide a percussion safety, which willpresent improved features over conventional mechanisms of this nature,and which will be simple, sturdy, easy to manufacture and to mount, andsafe in operation.

Other objects of the invention will be apparent hereinafter from thespecification and from the recital of the accompanying claim.

In the accompanying drawings there are illustrated, merely by way ofexample, several different embodiments of my new locking block.

In these drawings:

Fig. l is a fragmentary longitudinal section of a gun, showing animproved locking block made according to one embodiment of thisinvention in elevation in the position in which it locks the breechblock of the gun to the barrel extension;

Fig. 2 is a similar section but with the locking block in releasedposition;

Fig. 3 is a section taken at right angles to Fig. 1 and looking down onthe breech block;

Fig. 4 is a plan view showing a breech block of modified form having asomewhat difierent means from that of Fig. 3 for manually moving thelocking block to released position;

Figs. 5 and 6 are sections corresponding to Figs. 1 and 2, respectively,and showing a somewhat different embodiment of the invention; and

Fig. 7 is a section at right angles to Fig. 5, looking upon the breechblock and the means for manually moving the locking block to releasedposition.

Referring first to Figs. 1 to 3 inclusive, 29 denotes the barrel of thegun, and 30 designates the barrel-extension. The new locking block 1 isof approximately parallelpiped shape. it has a projecting tooth 1a whichis adapted to engage in the slot 31 in the barrel-extension 30 to lockthe barrel extension 30 to the breech block 3. The locking block 1 ishoused in the body of the breech block and it is hingedly connected tothe breech block by means of a pin 2. This pin is mounted in the breechblock and extends transversely thereof, and engages in an oblong slot 32in the locking block 1. The purpose of the oblong slot 32 is to allowfor a short sliding movement of the locking block longitudinally duringpivotal movement thereof. This permits a plane front face 33 to beprovided on the locking block 1 which is adapted to seat against a planeface on the breech block 3 so that the thrust of recoil may be taken bythe locking block, the breech block and the barrel extension and not betransmitted to the pin 2. Were the locking block to be pivoted to thebreech block by a pin 2 seating in a closely fitting circular hole inthe locking block, the pin 2 would take the thrusts and shock of recoil.There is an additional advantage in providing a plane front face on thelocking block, and that is that it facilitates very much the con-2,715,355 Patented Aug. 16, 1955 struction of both the locking block andthe breech block.

Inside the locking block there is provided a longitudinal hole 35 inwhich the percussion rod 10 is housed. This rod serves to transmitpercussion from the hammer 9 to the firing pin 11. The pin 11 isreciprocably mounted in the breech block 3 and is constantly urgedrearwardly by the coil spring 37. It is evident that if the lockingblock is in the unlocked position shown in Fig. 2, the percussion rod 10assumes such a position that even if it is struck by the hammer 9 itwill not strike the firing pin 11 because it is no longer aligned withsaid firing pin. Absolute assurance is had, therefore, that firing ofthe gun cannot take place if the breech block is not locked to the gunbarrel.

A spring 5a, for example, the recoil spring of the breech block, actsthrough a rod 5 and pin 4 to constantly urge the locking block towardlocking position. This spring surrounds a portion of the rod 5, which ispivoted at its front end by the pin 4 to the locking block. The spring5a is in such position as to create a leverage between the point ofapplication of the spring and the pivot of the locking block so that thespring, as stated, always pushes the locking block toward lockingposition.

The locking block is provided with a ledge 6, and with an ear orprojection 8. The ear or projection 8 is to permit movement of thelocking block manually to disengaged position. The ledge 6 is adapted tobe engaged by the cocking tooth 7 of the gun, upon return of the breechblock to battery position. The cocking tooth 7 is pivotally mounted bymeans of pin 37' in conventional manner upon a lever 38. It isconstantly urged clockwise (Fig. 2) about its pivot 37 by aspring-pressed pin 39, that is housed in conventional manner in thelever 38.

To manually release the locking block 1, the ear or projection 8 ispressed toward the gun stock to pivot the locking block downwardly anddisengage its tooth In from the slot 31 in the barrel extension 30. Thepivotal motion of the locking block 1, as already stated, is possiblenotwithstanding the fact that it has a plane bearing surface 33, thanksto the oblong slot 32 for the pivot pin 2. After the locking block 1 hascompleted its pivotal movement, as shown in Fig. 2, and its tooth 1ahas, thereby been disengaged from the barrel-extension, the breech block3 can be made to move rearwardly to the end of its stroke by continuingthe pressure upon the ear or projection 8. When the breech block 3reaches the position shown in Fig. 2, the cocking teeth 7 willautomatically engage the ledge 6 of the locking block to hold the breechblock in rear position. The cocking tooth 7 can be tripped throughconventional means to release the breech block again to permit thebreech block to return to battery.

The ear or projection 8 may be replaced, as shown in Fig. 4, by a smalltooth 15 that is formed integral with the locking block, and that may beengaged by a block 14 on a cooking carriage 13 that is slidable in thebreech block 3. The sliding carriage 13 may be provided with an ear orprojection 12 for manual actuation.

Assuming that the parts are in the position shown in Fig. 1, upon firingthe shot, the whole system comprising the barrel 29, thebarrel-extension 30, the breech block 3, and the locking block 1 whichlocks the breech block and barrel extension together, recoils to the endof the stroke. During return to battery of the whole system underactuation of the recoil spring, not shown in the drawing, the ledge 6 ofthe locking block is engaged by the cocking tooth 7, which causes thelocking block to pivot on the pin 2, unlocking the breech block from thebarrel and barrel-extension assembly. While the breech block is held bythe cocking tooth 7, then, the barrel-extension 30 and barrel 29 returnto battery. During the return stroke of the barrel and barrel-extensionassembly, the empty cartridge case 40 is retained by the extractors 41,which are mounted in known manner on the breech block; and thus theempty cartridge case is extracted from the gun barrel.

Upon reaching the end of the return stroke to battery, the barrel andbarrel-extension assembly operate through known means (not shown) uponthe cocking tooth 7 to disengage the cocking tooth from the ledge 6 ofthe locking block 1, permitting the breech block3 to return to itsforward position under'thrust of its own recoil spring. During thisreturn movement anew cartridge is introduced into the gun barrel inknown manner.

There is a small lever or detent 17 (Fig. 3 pivotally mounted by meansof pin 18 on the breech block 3. This lever or detent is constantlyurged by a coil spring 19 counter-clockwise from the position shown inFig. 3 so that when the tooth 1a of the locking block 1 is in disengagedposition (as shown in Fig. 2), the lever or detent 17 will be moved overthis tooth to retain the tooth in disengaged posiiton. Hence, after thelocking block 1 has been released from the cocking tooth 7, it is stillheld depressed by the lever or detent 17 during the return movement ofthe breech block 3 to battery. During this return movement, the tail ofthe lever or detent 17 travels in a slot 42 in the barrel extension 30;and when the breech block is approaching batteryv position, the tail ofthe lever or detent 17 rides on the cam surface 20 at the front end ofthe slot 42 so that the lever or detent 17 is rocked about its pivot pin18 in a clockwise direction to disengage it from the tooth 1a of thelocking block. This permits the locking block to be returned to lockingposition under actuation of the spring So when the tooth 1a of thelocking block registers with the slot 31 in the barrel-extension.

In the embodiment shown in Figs. 5, 6 and 7 the firing pin is integralwith the percussion rod 24. It is also provided with a laterallyextending lug 25 for safety control. The combined percussion rod andfiring pin 24 is guided in the breech block 3 at front and rear of thelocking block 1.

Here, the locking block 1' has an opening 50 extend ing longitudinallythrough it for the passage of the combined percussion rod and firing pin24. The opening locking block to pivot on its pivot pin 2' withouthitting the pin 24; and it is formed with an enlarged hole 26 whosebounding wall constitutes a cam surface which is adapted to engage andoperate on the lug 25 of the percussion rod 24. Upon downward pivotalmovement of the locking block 1, then, the percussion rod 24 is movedrearwardly far enough so that it cannot project beyond the front edge 45of the breech block 3', and so that, therefore, it cannot fire.

In this embodiment of the invention, the locking block 1. has no car orprojection for manual operation, but has instead a recess 22 in one sidesurface (Fig. 7) which is engaged by a tooth 21 of the manuallyreciprocable slide 46. This slide is mounted to slide in a guideway inthe breech block 3 and is manually movable rearwardly by pressing uponthe ear or projection 47.

The locking block 1' is mounted as in the embodiment of the inventionshown in Figs. 1 to 3 inclusive, a pin 2 is wide enough, as shown inFigs. 5 and 6 to permit the iii being provided in the breech block 3which extends transversely of the breech block and which engages in anelongated slot 32' in the locking block. As before the locking block hasa tooth 1a which is adapted to engage in the locking slot 31 of thebarrel-extension 30. The tooth la is disengaged by pressing the ear orprojection 47 rearwardly to rock the locking block downwardly in amanner similar to the operation of the first described embodiment of theinvention. The locking block may be held in downward position by alever, similar to the lever 17 of Fig. 3 which is disengaged by a camsurface as in the first described embodiment of the invention. Thelocking lever 17 is shown in dotted lines in Fig.7. The locking lever 17cooperates with the top of the locking tooth 1a in the same manner as inthe first described embodiment of the invention, and as illustrated inFig. 3.

Having thus described my invention, what I claim is:

In a recoil-operated gun, the combination with a recoilingbarrel-extension having a locking 'slo't therein, and abreech-blockreciprocable axially in and relative to said barrelextension, of a locking block mounted in said breech block and having alocking tooth formed thereon to engage in said locking slot to lock saidbreechblock to said barrel extension, said locking block being mountedin said breech block for pivotal and sliding movements relative to saidbreech block, the pivotal and sliding mounting for the locking blockcomprising a pivot pin secured to one of the two named blocks and anelongate slot formed in the other named block in which said pin engages,a percussion rod slidable longitudinally in said locking block anddisposed to be in operative, firing position when said locking tooth isengaged in said locking slot, resilient means for rocking said lockingblock in one direction about said pivot pin to move said locking toothinto locking engagement with said locking slot, and means for rockingsaid locking block in the opposite direction about its pivot todisengage said locking tooth from said locking slot, said locking blockhaving a plane front surface, and said breech block having a planesurface against which said plane front surface is adapted to abut andseat when said locking tooth is in engagement with said locking slot,said plane surfaces and said elongate slot permitting the thrust ofrecoil to be taken by the locking block, the breech block, and thebarrel extension without being transmitted to said pivot ReferencesCited in the file of this patent UNITED STATES PATENTS 324,296 BrowningAug. 11, 1885 768,665 Johnson Aug. 30, 1904 1,984,443 Swebilius Dec. 18,1934 2,090,340 Browning Aug. 17, 1937 2,352,193 Gorton a- June 27, 19442,527,895 Tassan Oct. 31, 1950 2,614,462 Browning Oct. 21, 1952 FOREIGNPATENTS 134,191 Germany Apr. 11, 1907

